/* Copyright (c) 2020 XEPIC Corporation Limited */
/*
 * Copyright (c) 2005-2011 Stephen Williams (steve@icarus.com)
 *
 *    This source code is free software; you can redistribute it
 *    and/or modify it in source code form under the terms of the GNU
 *    General Public License as published by the Free Software
 *    Foundation; either version 2 of the License, or (at your option)
 *    any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
 * USA.
 */

/*
 * This file includes functions for evaluating REAL expressions.
 */
#include <stdlib.h>
#include <string.h>

#include "vvp_config.h"
#include "vvp_priv.h"
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif

#ifdef HAVE_INTTYPES_H
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS 1
#endif
#include <inttypes.h>
#else
#endif

#include <assert.h>
#include <math.h>

/*
 * Evaluate the bool64 the hard way, by evaluating the logic vector
 * and converting it to a bool64.
 */
static int eval_bool64_logic(ivl_expr_t expr) {
  int res;
  const char* s_flag = "";

  draw_eval_vec4(expr);
  res = allocate_word();
  if (ivl_expr_signed(expr)) s_flag = "/s";

  fprintf(vvp_out, "    %%ix/vec4%s %d;\n", s_flag, res);

  return res;
}

static int draw_number_bool64(ivl_expr_t expr) {
  int res;
  const char* bits = ivl_expr_bits(expr);
  uint64_t val = 0;
  unsigned long idx, low, hig;

  for (idx = 0; idx < ivl_expr_width(expr); idx += 1) {
    if (bits[idx] == '1') val |= 1UL << idx;
  }

  res = allocate_word();
  low = val % UINT64_C(0x100000000);
  hig = val / UINT64_C(0x100000000);
  fprintf(vvp_out, "    %%ix/load %d, %lu, %lu;\n", res, low, hig);
  return res;
}

int draw_eval_bool64(ivl_expr_t expr) {
  int res;

  switch (ivl_expr_type(expr)) {
    case IVL_EX_NUMBER:
      res = draw_number_bool64(expr);
      break;
    default:
      res = eval_bool64_logic(expr);
      break;
  }

  return res;
}
